I am going to rebarrel my 28N to a 30N, part of what made the decision easy is that when I was at the gunsmith to discuss it (and pick up another gun they were doing work on, a 30-06 randomly enough) they had ADG brass and enough Berger 215's to last a good while. I had already bought dies at Midway when they were in stock in this shortage, figuring I could sell them for what I paid if I needed to. So I had all the components I would need.
I have a 280ai on order from Dallas Lane and I wanted to have the powder he typically uses in his 280ai's and that will match his load work up, so I opportunistically looked for, and found, several powders I didn't have. This is to replace another 280ai I have.
Having said all that, maybe you could hold off ordering for a few weeks and see what you can come across for your 280ai. Seems like a good bit of powder hit shelves about 2-3 months ago...maybe another big batch will come in (Hodgdon is usually pretty good at telling you ballpark times for when they may get some more to distribute). You could also look for bullets and brass and buy when you find some at retail or close to it, or post a 'wanted to buy' ad in the classifieds. If you couldn't find all the components before you have to decide, you could resell that stuff to get your money back if you pay MSRP, maybe you will be out shipping costs but I doubt it. And in Texas I would think powder would be easy to sell locally.
long story short...if you want to give it some time, buy components for a 280ai, resell at your cost if you have to. Worst case is you are out maybe $25 in shipping for everything, but think of it as a $25 option to have what you really want, which it sounds like is a 280ai. I've 'settled' on a gun, and by that I mean I bought what was practical (a 30-06) instead of what I wanted (280ai), and a few years later I had the itch to get what I really wanted all along (and now I have both
). A new rifle costs a lot more than $25.